Bone china

Description

A strong, ivory-white, translucent porcelain made with kaolin and about 25-50% bone ash. Bone china was invented by Josih Spode in the 1740s in England. While trying to duplicate Chinese porcelain, he discovered that china clay could be strengthened during and after firing with the addition of bone ash. Bone ash is a white calcium phosphate powder obtained from calcined cattle bones. Bone china is biscuit-fired at 1250-1300 C then glost fired with a lead or borax glaze at 900-1000 C.